1. Field of the Invention
This invention concerns the mount construction of foam substrates inside a hollow structure. It involves the mount construction for installing a foam substrate that insulates a hollow space by foam expansion from external heat inside a hollow space of a hollow structure for the primary purpose of providing vibration proofing and noise proofing in a hollow, box-shaped, closed cross-sectional space that is formed by multiple panels, such as vehicle body pillars, rocker panels, roof side panels, etc.
2. Prior Art
An example of the type of mount construction for a foam substrate in a hollow structure is disclosed in Patent Disclosure Bulletin Heisei 7 (1995) -232664.
In this example, and as shown in FIG. 9 hereof, a mount component 113, which is composed of a bottom panel 114 and two walls 112, 112' forms an abridged U-shaped cross section. A groove 114a is created in the center of the upper surface of the bottom panel 114 of the mount component 113, while the foam substrate 111 is fixed to the bottom panel 114 by a part of its lower surface 111a being fitted into the aforementioned groove 114a.
Furthermore, a flat panel-shaped magnet 126 is attached to the lower surface of the bottom panel 114, so as to attach the mount component, with the foam substrate 111 affixed onto the inner wall surface of a hollow structure through the magnetic force of the magnet 126.
As the foam substrate 111 foam-expands from heat from outside of the hollow structure, the direction of the foam developed by the foam substrate 111 is controlled by the two side walls 112, 112' of the mount component 111. As a result, the foam substrate 111 foam-expands into a foam substance in a direction orthogonal to the longitudinal direction of the hollow space inside the hollow structure, thus, efficiently insulating the hollow space.
In the aforementioned conventional mount construction, the design requires fitting a part of the lower surface of the foam substrate into a groove which is created approximately in the center of the bottom panel of the mount component. It is difficult to achieve stable attachment of the foam substrate to the mount component. In some cases, the foam substrate unexpectedly separates from the groove.
Furthermore, the mount component is made in one piece which consists of a bottom panel for installing the foam substrate and two side walls for controlling foam development of the foam substrate. A large amount of resin material is required to produce such a mount component from synthetic resin materials, thus resulting in a higher cost.